Babesiosis: Tick-Borne Infection Canadians Should Know About

Babesiosis is an infection that affects red blood cells and is caused by the single-celled protozoan parasite Babesia. The infection can lead to headache, fever, fatigue, chills, and body aches. Although babesiosis is uncommon in Canada, cases have been reported, particularly in regions where deer ticks are present.

Babesia parasites live and multiply inside red blood cells, eventually destroying them. The infection is spread through the bite of infected blacklegged (deer) ticks, the same ticks responsible for transmitting Lyme disease. While babesiosis is far more common in animals, human cases are increasing in parts of North America due to climate change and expanding tick habitats.

Signs and Symptoms of Babesiosis

Many people—especially healthy individuals under the age of 40—may have no noticeable symptoms. When symptoms do occur, they may include:

• Fever and chills

• Headache

• Fatigue and weakness

• Muscle or joint pain

• Sweating

• Loss of appetite

In more noticeable cases:

• Jaundice (yellowing of the skin or whites of the eyes) may develop

• Anemia can occur due to destruction of red blood cells

• The liver and spleen may enlarge

In some cases, there is headache, fever, fatigue, and muscle or joint pain.

Who Is at Higher Risk?

Severe babesiosis is more likely to occur in:

• Individuals who have had their spleen removed

• Older adults

• People with weakened immune systems, including those with HIV/AIDS

• Individuals undergoing chemotherapy or immunosuppressive therapy

In high-risk individuals, babesiosis can resemble malaria and may cause:

• High fever

• Dark urine

• Severe anemia

• Jaundice

• Kidney failure

In rare cases, the condition can be life-threatening without prompt medical care.

How Babesiosis Is Diagnosed

Diagnosis is typically made through a blood test, where a sample is examined under a microscope to identify the parasite within red blood cells. Additional blood tests may be used to assess anemia and organ function.

Management and Treatment

• Mild cases in healthy individuals may resolve on their own without treatment.

• Symptomatic cases are commonly treated with:

  • Atovaquone and azithromycin (first-line treatment with fewer side effects)

  • In more severe cases, quinine and clindamycin may be used

Hospital care may be required for severe infections, particularly if complications such as anemia or kidney issues develop.

Prevention: Reducing Risk in Canada

In Canadian regions where deer ticks are present, babesiosis risk can be reduced by following tick-prevention strategies:

• Wear long sleeves and pants when hiking or camping

• Use insect repellents approved in Canada

• Perform full-body tick checks after outdoor activities

• Shower soon after spending time in wooded or grassy areas

• Promptly and safely remove any attached ticks

Why This Matters in First Aid & Safety Training

Babesiosis highlights the importance of:

• Recognizing fever, fatigue, and anemia-related symptoms

• Understanding tick-borne illness risks

• Knowing when medical care is required

• Practicing outdoor and wilderness safety

First aid and CPR training in Canada helps individuals identify serious medical conditions early, manage symptoms safely, and seek appropriate care.

Important Disclaimer

For Educational Purposes Only
The information on this page is intended for general education and first aid awareness. It does not replace medical advice, diagnosis, or treatment. Anyone experiencing persistent fever, fatigue, jaundice, or symptoms following a tick bite should seek medical care promptly.

First aid training supports early recognition of illness and safe response but does not replace professional medical treatment.